Clinical outcomes of gemcitabine plus nab-paclitaxel (GnP) in initially diagnosed locally advanced pancreatic cancer.

Abstract

407 Background: Gemcitabine plus nab-Paclitaxel has shown improved survival in patients with metastatic pancreatic cancer in MPACT. Many studies have been investigating the survival benefit of GnP in LACP patients. The aim of this study is to clinical outcome of GnP in initially diagnosed LAPC in our single tertiary institution. Methods: LACP patients who received GnP as initial chemotherapy were identified between December 2014. and December 2016 from our database retrospectively. Demographic characteristics, disease status, response, conversion to resection and survival was reviewed. Resectability was determined at our hepatobiliary pancreatic tumor board, reflecting Japanese guideline of pancreatic cancer. Results: We identified 55 LACP patients initially treated with GnP (median age: 67 year old, female was 49%, ECOG PS 0/1, 62%/38%, pancreatic head 58%, baseline tumor size: median 32mm (18-62), CA19-9: median 139ng/ml (3.9-12956)). Best objective response rate was 58% and median time to partial response was 60 days (40-212). Median overall survival (mOS) was 24.7 months (95%CI :15.5-not reached). Nine patients (16%:9/55) were re-evaluated as resectable with CT and normalized CA19-9/CEA and subsequently proceeded to conversion to resection. Seven patients (13%:7/55) achieved R0 resection and sequentially performed adjuvant six- month duration of GnP. Median time to resection from initial GnP administration was 5.2 months (4.0-7.3). LAPC patients who achieved conversion to resection was associated with better overall survival than non-resected LAPC in log-rank test (mOS: all alive :12.1-25.4months vs 21.5 months 95%Cl:15.5-, HR:0.493 range: NA, P = 0.043). Shrinking tumor minimal size from the baseline was the factor to successful conversion in univariate analysis (P = 0.006). Conclusions: GnP showed promising results of response and overall survival in uLAPC patients. Conversion to resection in carefully selected uLAPC currently suggests an early surgical benefit, but longer follow-up and more cases will be required to assess the potential long-term benefit of conversion therapy.